DO IT, ROCKAPELLA. We celebrate our half-birthday milestone by talking about our favorite world landmarks: Eiffel Tower, Great Wall of China, Giza Pyramids, and Chris reveals his Statue of Liberty obsession. And of course, the gang relives the golden sleuthing days of Carmen Sandiego. ALSO: Our new favorite words, special edition listener challenge, easy trick for memorizing the colors of the eBay and Google logos in order